Stay with a 95 or older unit as they are not electronic like the 96 and newer which will require a trans controller. 95 and back you can use two toggle switches, one each for the od and lockup. Some people have rigged up ways to operate them so they are a more automatically done shift to od/lu otherwise if you don't have a way to switch the new features it will just shift right in to od/lu when you are hardly moving. Some of the earlier units were od only and ran a standard non lu converter. Trans Go had instructions in their shift kits to modify the lube passages in the earlier units to prevent lack of lube issues that were a problem on some transmissions. If you run the numbers down, some applications had a more hd trans than others with features like more frictions discs, stouter planetary assemblies etc. The best v8 units were behind the 5.9's aka 360's. Even better for internals were the v10 and cummins units if you are going for the gusto. Since the 95 and older units were hydraulic, shift kits were easier and make more of an improvement which will help trans life. Another cheap and sometimes free improvement for the 97 and older units is to get a pan off the 98 and newer trans which is deeper and adds 2qts to you fluid capacity. You can find them at the diesel specialty shops or trans shops when someone puts a deeper aluminum pan on their cummins trucks. Do this for the regular 727's also but for them you need a filter extension.